Wireless IC device and component for wireless IC device

ABSTRACT

A wireless IC device includes a wireless IC chip, a power supply circuit board upon which the wireless IC chip is mounted, and in which a power supply circuit is provided, the power supply circuit includes a resonant circuit having a predetermined resonant frequency, and a radiation pattern, which is adhered to the underside of the power supply circuit board, for radiating a transmission signal supplied from the power supply circuit, and for receiving a reception signal to supply this to the power supply circuit. The resonant circuit is an LC resonant circuit including an inductance device and capacitance devices. The power supply circuit board is a multilayer rigid board or a single-layer rigid board, and between the wireless IC chip and the radiation pattern is connected by DC connection, magnetic coupling, or capacitive coupling.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a wireless IC device, and particularly,to a wireless IC device used for an RFID (Radio FrequencyIdentification) system, and a component used for the wireless IC device.

2. Description of the Related Art

In recent years, for an inventory item management system, an RFID systemhas been developed which includes a reader/writer for generating adielectric magnetic field and an IC tag (hereafter, referred to aswireless IC device) for storing predetermined information about aninventory item which communicate with one another via a non-contactmethod, thereby transmitting information. Known wireless IC devices usedin RFID systems are described in Japanese Unexamined Patent ApplicationPublication No. 2005-136528 (Patent Document 1) and Japanese UnexaminedPatent Application Publication No. 2005-244778 (Patent Document 2), forexample.

The wireless IC device shown in FIG. 59 includes an antenna pattern 301provided on a plastic film 300, and a wireless IC chip 310 is attachedto one end of the antenna pattern 301, and the wireless IC device shownin FIG. 60 includes an antenna pattern 321 and a radiation electrode 322provided on a plastic film 320, and a wireless IC chip 310 is attachedto a predetermined portion of the antenna pattern 321.

However, with the conventional wireless IC devices, the wireless IC chip310 is connected to and mounted on the antenna pattern 301 or 321 usingan Au bump in a DC manner. Thus, it is necessary to determine theposition of the small wireless IC chip 310 on the film 300 or 320 havinga large area. However, it is extremely difficult to mount the wirelessIC chip 310 on the large-area film 300 or 320. Thus, positionaldeviation at the time of mounting causes the resonant frequencyproperties at the antenna to be changed. The resonant frequencyproperties at the antenna are also changed by the antenna pattern 301 or321 being rounded, or being sandwiched between dielectric members (e.g.,inserted into a book).

SUMMARY OF THE INVENTION

To overcome the problems described above, preferred embodiments of thepresent invention provide a wireless IC device having stable frequencyproperties, and components which can be used for the wireless IC device.

A wireless IC device according to a first preferred embodiment of thepresent invention includes a wireless IC chip, a power supply circuitboard connected to the wireless IC chip and including a power supplycircuit which includes a resonant circuit having a predeterminedresonant frequency, a radiation pattern, to which the power supplycircuit board is attached or disposed adjacent, the radiation patternbeing arranged to radiate a transmission signal supplied from the powersupply circuit, and/or to receive a reception signal and supply thereception signal to the power supply circuit.

With the wireless IC device according to the first preferred embodiment,the wireless IC chip and the power supply circuit board are disposed ona wiring board so as to be substantially parallel to one another, andare connected via a conductor disposed on the wiring board.

A wireless IC device according to a second preferred embodiment includesa wireless IC chip, a power supply circuit board upon which the wirelessIC chip is mounted and having a power supply circuit which includes aresonant circuit having a predetermined resonant frequency, and aradiation pattern to which the power supply circuit board is attached ordisposed adjacent, the radiation pattern being arranged to radiate atransmission signal supplied from the power supply circuit, and/or toreceive a reception signal and supply the reception signal to the powersupply circuit.

With the wireless IC devices according to the first and second preferredembodiments of the present invention, the frequency of the transmissionsignal radiated from the radiation pattern, and the frequency of thereception signal supplied to the wireless IC chip are substantiallydetermined by the resonant frequency of the resonant circuit in thepower supply circuit board. The term “substantially determined” is useddue to the frequency being minutely shifted due to the positionalrelationship between the power supply circuit board and the radiationpattern in some cases. That is to say, the frequencies of thetransmission and reception signals are determined by the power supplycircuit board, so that the frequency properties thereof are not changedregardless of the shape, size, and placement position of the radiationpattern, e.g., even if the wireless IC device is rounded, or sandwichedbetween dielectric members. Consequently, stable frequency propertiesare obtained.

With the wireless IC device according to the second preferredembodiment, the wireless IC chip is mounted on the power supply circuitboard, and provided on the radiation pattern via the power supplycircuit board. The power supply circuit board is considerably smaller inarea as compared to the radiation pattern, such that the wireless ICchip can be mounted on the power supply circuit board with extremelyhigh precision.

With the wireless IC devices according to the first and second preferredembodiments, the radiation pattern may be disposed on both sides of thepower supply circuit board. Energy radiated from the power supplycircuit can be propagated along both sides of the radiation pattern bysandwiching the power supply circuit board with the two radiationpatterns, thereby improving gain.

The resonant circuit may be a distributed-constant-type resonantcircuit, or a concentrated-constant-type resonant circuit including acapacitor pattern and an inductor pattern. The distributed-constant-typeresonant circuit includes an inductor defined by a strip line or othersuitable structure. Particularly, design of the resonant circuit isfacilitated when the transmission and reception signals are included ina high-frequency band not less than 5 GHz. Therefore, thedistributed-constant-type resonant circuit is advantageous.

The concentrated-constant-type resonant circuit may be an LC seriesresonant circuit or LC parallel resonant circuit, or may be configuredso as to include multiple LC series resonant circuits or multiple LCparallel resonant circuits. When the resonant circuit is defined by theconcentrated-constant-type resonant circuit including a capacitorpattern and an inductor pattern, the resonant circuit can be readilydesigned in a low-frequency band not greater than 5 GHz where thetransmission and reception signals are included, and the resonantcircuit is not affected by influences from other devices, such as aradiation pattern. When the resonant circuit includes multiple resonantcircuits, the respective resonant circuits are coupled, thereby wideningthe bandwidth of the transmission signal.

Also, when the capacitor pattern is disposed downstream of the wirelessIC chip and between the wireless IC chip and the inductor pattern, surgeresistance improves. A surge is a low-frequency current up to about 200MHz, which can be reduced by a capacitor or other suitable element, andthe surge breakdown of the wireless IC chip can be prevented.

The capacitor pattern and the inductor pattern may be arrangedsubstantially in parallel to the radiation pattern. That is to say, thecapacitor pattern and the inductor pattern are not disposed along astraight line on which the radiation pattern is disposed, such that theelectric field formed by the capacitor pattern, and the magnetic fieldformed by the inductor pattern are directly applied to the radiationpattern, and thus, the magnetic field formed by the inductor pattern isnot obstructed by the capacitor pattern, whereby radiant efficiency fromthe inductor pattern is improved. Further, a reflector and/or wavedirector may be disposed at a portion where the magnetic field is formedby the inductor pattern. Thus, the radiation properties and directivityfrom the power supply circuit to the radiation pattern are easilyadjusted, and external electromagnetic influence is eliminated to thegreatest extent possible so as to obtain stability of the resonantproperties.

The power supply circuit board may be a multilayer board in whichmultiple dielectric layers or multiple magnetic layers are stacked, andthe capacitor pattern and the inductor pattern are disposed on thesurface and/or inside the multilayer board. The resonant circuitincludes a multilayer board, whereby the devices (electrode patterns,etc.) defining the resonant circuit can be provided not only on thesurface but also inside of the board. Thus, the size of the board can bereduced. In addition, flexibility of the layout of the resonant circuitdevice is improved, and the capabilities of the resonant circuit areenhanced. The multilayer board may be a resin multilayer board includingmultiple stacked resin layers, or may be a ceramic multilayer boardincluding multiple stacked ceramic layers. The multilayer board may be athin-film multilayer board using a thin-film forming technology. Whenusing the ceramic multilayer board, ceramic layers are preferably madeof a low-temperature sintering ceramic material, such that silver orcopper having low resistance values can be used as a resonant circuitmember.

On the other hand, the power supply circuit board may be a dielectric ormagnetic single-layer board, and the capacitor pattern and/or inductorpattern are provided on the surface of the single-layer board. Thematerial of the single-layer board may be a resin or ceramic. Thecapacitance by the capacitor pattern may be provided between theplane-shaped electrodes provided on both sides of the single-layerboard, or may be provided between the electrodes disposed substantiallyin parallel on one side of the single-layer board.

The power supply circuit board is preferably a rigid board. With a rigidboard, even if the wireless IC device is adhered to any shaped inventoryitem, the frequency of the transmission signal is stabilized. Moreover,the wireless IC chip can be mounted on a rigid board in a stabilizedmanner. On the other hand, the radiation pattern is preferably made of aflexible metal film. The wireless IC device can be adhered to any shapedarticles as long as the radiation pattern is flexible.

Furthermore, when the flexible metal film is retained in a flexibleresin film, the wireless IC device itself is easily handled.Particularly, when the wireless IC chip, power supply circuit board, andradiation pattern are covered by the film, these components areprotected from the external environment.

Incidentally, the electric length of the radiation pattern is preferablyan integer multiple of a half wavelength of the resonant frequency,whereby gain is increased to the greatest extent. However, the frequencyis substantially determined by the resonant circuit, so that it is notrequired that the electric length of the radiation pattern be an integermultiple of a half wavelength of the resonant frequency. This is anadvantage as compared to a wireless ID device in which the radiationpattern is an antenna device having a particular resonant frequency.

Also, various arrangements may be used for the connection between thewireless IC chip and the power supply circuit board. For example, anarrangement may be used in which the wireless IC chip is provided with achip-side electrode pattern, the power supply circuit board is providedwith a first-board-side electrode pattern, and the chip-side electrodepattern and the first-board-side electrode pattern are connected by DCconnection. In this case, the connection may be made by soldering, anelectroconductive resin, or gold bump, for example.

Alternatively, the chip-side electrode pattern and the first-board-sideelectrode pattern may be connected with capacitive coupling or magneticcoupling. When the connection is with capacitive coupling or magneticcoupling, soldering or an electroconductive resin is not required, butan adhesive agent such as a resin or other suitable agent is preferablyused for adhesion. In this case, the chip-side electrode pattern and thefirst-board-side electrode pattern need not be formed on the surface ofthe wireless IC chip, and on the surface of the power supply circuitboard. For example, a resin film may be formed on the surface of thechip-side electrode pattern, or the first-board-side electrode patternmay be formed on an inner layer of the multilayer board.

With capacitive coupling, the area of the first-board-side electrodepattern is preferably greater than the area of the chip-side electrodepattern. Even if the positional accuracy varies somewhat at the time ofmounting the wireless IC chip on the power supply circuit board,variations in capacitance between both electrode patterns are greatlyreduced. Moreover, it is difficult to form an electrode pattern having alarge area on the small wireless IC chip. However, the power supplycircuit board is relatively large. Thus, an electrode pattern having alarge area can be formed without any obstructions.

With magnetic coupling, the required accuracy for mounting the wirelessIC chip to the power supply circuit board is not as high as that withcapacitive coupling, which further facilitates mounting. Also, thechip-side electrode pattern and the first-board-side electrode patternare preferably coil-shaped electrode patterns. In this case, acoil-shaped electrode pattern such, as spiral, helical or other suitableshape facilitates design. With a high frequency, a meander-shapedelectrode pattern is preferable.

On the other hand, various types of arrangements may be used for theconnection between the power supply circuit board and the radiationpattern. For example, the power supply circuit board may be providedwith a second-board-side electrode pattern, and the second-board-sideelectrode pattern and the radiation pattern may be connected by DCconnection. In this case, connection can be made using soldering, anelectroconductive resin, gold bump, or other suitable method.

Alternatively, the second-board-side electrode pattern and the radiationpattern may be connected with capacitive coupling or magnetic coupling.With capacitive coupling or magnetic coupling, it is not necessary touse soldering or an electroconductive resin, however an adhesive agentsuch as a resin or other suitable agent must be used for adhesion. Inthis case, it is also unnecessary for the second-board-side electrodepattern to be formed on the surface of the power supply circuit board.For example, the second-board-side electrode pattern may be formed on aninner layer of the multilayer board.

With magnetic coupling, the second-board-side electrode pattern ispreferably a coil-shaped electrode pattern. A coil-shaped electrodepattern, such as spiral, helical, or other suitable shape facilitatescontrol of magnetic flux, thereby facilitating design. With a highfrequency, a meander-shaped electrode pattern may be provided. Withmagnetic coupling, it is preferable not to obstruct variations ofmagnetic flux that occur at the second-board-side electrode pattern(coil-shaped electrode pattern), for example, it is preferable toprovide an opening portion in the radiation pattern. Thus, thepropagation efficiency of signal energy is improved, and a frequencyshift due to adhesion between the power supply circuit board and theradiation pattern is reduced.

When the second-board-side electrode pattern is a coil-shaped electrodepattern, the winding axis thereof may be arranged substantially parallelor substantially perpendicular to the radiation pattern. With thelatter, the winding width of the coil-shaped electrode pattern ispreferably configured so as to gradually increase toward the radiationpattern.

With the wireless IC devices according to the first and second preferredembodiments, if the radiation pattern is a both-side (both-end) opentype radiation pattern including a radiation portion for performingexchange of external transmission/reception signals, and a power supplyportion for performing exchange of a transmission/reception signal withthe power supply circuit (resonant circuit), antenna gain is improved bythe radiation portion, whereby even a small power supply circuit patternobtains sufficient gain, the wireless IC device operates with at asufficient distance from the reader/writer, and even a frequency bandnot less than the UHF band is sufficient for use. Also, the resonantfrequency is primarily determined by the power supply circuit pattern,the shape of the radiation portion can be varied, gain can be adjustedby the size of the radiation portion, and the center frequency can befinely adjusted with the shape of the radiation portion.

In addition, at least a portion of the power supply portion of theradiation pattern is arranged so as to be disposed within the projectionplane of the power supply circuit pattern, and the area of the powersupply portion may be less than the area of the projection plane of thepower supply circuit pattern. Here, the term “projection plane” means aplane surrounded by the outline of the power supply circuit pattern, andthe term “the area of the power supply portion” means the area of themetal portion of the radiation pattern. When the power supply portion ofthe radiation pattern and the power supply circuit pattern are coupledvia magnetic field, when the area of the power supply portion is lessthan the area of the projection plane of the power supply circuitpattern, a portion obstructing the magnetic flux of the power supplycircuit pattern is reduced, whereby the propagation efficiency ofsignals improves.

Furthermore, with the power supply portion, the length of thelongitudinal direction thereof may be arranged, for example, in astraight-line shape so as to cross the projection plane of the powersupply circuit pattern. The radiation portion of the radiation patternmay be provided on both end sides of the power supply portion, or may beprovided on one end side of the power supply portion. When the radiationportion is provided on both end sides of the power supply portion, thecapacitive connectivity to the power supply circuit pattern is strong.When the radiation portion is provided on only one end side of the powersupply portion, the magnetic connectivity to the power supply circuitpattern is strong, and gain increases.

Also, multiple power supply circuit patterns may be formed on the powersupply circuit board, and the power supply portion of the radiationpattern is preferably disposed between the respective projection planesof the multiple power supply patterns. With the power supply portion,the length of the longitudinal direction thereof may be formed, forexample, in a straight-line shape so as to cross the respectiveprojection planes of the multiple power supply circuit patterns. Whenthe power supply portion is disposed between the multiple power supplycircuit patterns, the amount of electric power supply between the powersupply portion and the power supply circuit pattern increases.

The radiation pattern may be formed within a x-y plane, and may includethe radiation portion extending in the X-axis direction and Y-axisdirection. Thus, circularly-polarized waves can be received, and antennagain improves. On the other hand, the radiation pattern may include theradiation portion extending in the X-axis direction, Y-axis direction,and Z-axis direction, in an x-y-z space. In the event that the radiationportion extends three-dimensionally, transmission/reception can beperformed effectively in any direction.

Also, the radiation portion of the radiation pattern may extend in asubstantially perpendicular direction relative to the plane of the powersupply circuit pattern. That is to say, the power supply portion may beprovided within a plane which is the tip of the needle-shaped radiationportion, and is substantially perpendicular to the radiation portion,and this power supply portion and the power supply circuit pattern maybe connected via electric field or magnetic field. Thus, the wireless ICdevice can be attached to an article such that the needle-shapedradiation portion is inserted into the inventory item.

The power supply portion and the power supply circuit pattern may becovered with a magnetic member. Thus, leakage of electromagnetic energyis prevented, and the coupling between the power supply portion and thepower supply circuit pattern is improved, which produces improvedantenna gain.

A component for a wireless IC device according to a third preferredembodiment includes a wireless IC chip, and a power supply circuit boardincluding a power supply circuit, the power supply circuit board beingconnected to the wireless IC chip, and including a resonant circuithaving a predetermined resonant frequency.

A component for a wireless IC device according to a fourth preferredembodiment includes a wireless IC chip, and a power supply circuit boardmounting the wireless IC chip, the power supply circuit board includinga power supply circuit and a resonant circuit having a predeterminedresonant frequency.

According to the first and second preferred embodiments, the wireless ICchip can be mounted on the wiring board or power supply circuit boardwith extremely high precision. Also, the frequency of a transmission orreception signal is determined by the power supply circuit provided onthe power supply circuit board, whereby stable frequency properties areobtained without changing the frequency properties, even if the wirelessIC device is rounded, or sandwiched between dielectric members.

According to the third and fourth preferred embodiments, the wireless ICdevices according to the first and second preferred embodiments areappropriately configured.

Other features, elements, steps, characteristics and advantages of thepresent invention will become more apparent from the following detaileddescription of preferred embodiments of the present invention withreference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a first preferred embodimentof the wireless IC device according to the present invention.

FIG. 2 is a cross-sectional view of the first preferred embodiment ofthe present invention.

FIG. 3 is an equivalent circuit diagram of the first preferredembodiment of the present invention.

FIG. 4 is an exploded perspective view illustrating the power supplycircuit board of the first preferred embodiment of the presentinvention.

FIGS. 5A and 5B are perspective views illustrating connectionarrangements between a wireless IC chip and the power supply circuitboard.

FIG. 6 is a perspective view illustrating modification example 1 of theradiation pattern.

FIG. 7 is perspective view illustrating modification example 2 of theradiation pattern.

FIG. 8 is a plan view illustrating a second preferred embodiment of thewireless IC device according to the present invention.

FIGS. 9A and 9B illustrate a third preferred embodiment of the wirelessIC device according to the present invention, wherein FIG. 9A is a planview in a developed state, and FIG. 9B is a perspective view at the timeof usage.

FIG. 10 is a perspective view illustrating a fourth preferred embodimentof the wireless IC device according to the present invention.

FIG. 11 is a perspective view illustrating a fifth preferred embodimentof the wireless IC device according to the present invention.

FIG. 12 is a cross-sectional view illustrating a sixth preferredembodiment of the wireless IC device according to the present invention.

FIG. 13 is an equivalent circuit diagram illustrating a seventhpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 14 is an equivalent circuit diagram illustrating an eighthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 15 is an equivalent circuit diagram illustrating a ninth preferredembodiment of the wireless IC device according to the present invention.

FIG. 16 is a cross-sectional view illustrating a tenth preferredembodiment of the wireless IC device according to the present invention.

FIG. 17 is an equivalent circuit diagram of the tenth preferredembodiment of the present invention.

FIG. 18 is an exploded perspective view illustrating a power supplycircuit board of the tenth preferred embodiment of the presentinvention.

FIG. 19 is an equivalent circuit diagram illustrating an eleventhpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 20 is an equivalent circuit diagram illustrating a twelfthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 21 is an exploded perspective view illustrating the power supplycircuit board of the twelfth preferred embodiment of the presentinvention.

FIG. 22 is a perspective view illustrating a thirteenth preferredembodiment of the wireless IC device according to the present invention.

FIG. 23 is a cross-sectional view illustrating a fourteenth preferredembodiment of the wireless IC device according to the present invention.

FIG. 24 is an exploded perspective view illustrating the power supplycircuit board of the fourteenth preferred embodiment of the presentinvention.

FIG. 25 is an equivalent circuit diagram illustrating a fifteenthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 26 is an exploded perspective view illustrating the power supplycircuit board of the fifteenth preferred embodiment of the presentinvention.

FIG. 27 is an equivalent circuit diagram illustrating a sixteenthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 28 is an exploded perspective view illustrating the power supplycircuit board of the sixteenth preferred embodiment of the presentinvention.

FIG. 29 is an equivalent circuit diagram illustrating a seventeenthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 30 is an exploded perspective view illustrating the power supplycircuit board of the seventeenth preferred embodiment of the presentinvention.

FIG. 31 is a graph illustrating reflection properties of the seventeenthpreferred embodiment of the present invention.

FIG. 32 is an equivalent circuit diagram illustrating an eighteenthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 33 is an exploded perspective view illustrating the power supplycircuit board of the eighteenth preferred embodiment of the presentinvention.

FIGS. 34A and 34B illustrate the wireless IC chip of the eighteenthembodiment; FIG. 34A is a bottom view, and FIG. 34B is an enlargedcross-sectional view.

FIG. 35 is an equivalent circuit diagram illustrating a nineteenthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 36 is an exploded perspective view illustrating the power supplycircuit board of the nineteenth preferred embodiment of the presentinvention.

FIG. 37 is an exploded perspective view illustrating a twentiethpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 38 is a bottom view of the power supply circuit board upon which ismounted the wireless IC chip with the twentieth preferred embodiment ofthe present invention.

FIG. 39 is a side view of the twentieth preferred embodiment of thepresent invention.

FIG. 40 is a side view illustrating a modification example of thetwentieth preferred embodiment of the present invention.

FIG. 41 is a perspective view illustrating a first arrangement with themodification example illustrated in FIG. 40.

FIG. 42 is a perspective view illustrating a second arrangement with themodification example illustrated in FIG. 40.

FIG. 43 is an exploded perspective view illustrating a twenty-firstpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 44 is an equivalent circuit diagram illustrating a twenty-secondpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 45 is an exploded perspective view illustrating the power supplycircuit board of the twenty-second preferred embodiment of the presentinvention.

FIG. 46 is an exploded perspective view illustrating the power supplycircuit board according to a twenty-third preferred embodiment of thewireless IC device according to the present invention.

FIG. 47 is an equivalent circuit diagram illustrating a twenty-fourthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 48 is a perspective view illustrating the power supply circuitboard of the twenty-fourth preferred embodiment of the presentinvention.

FIG. 49 is an equivalent circuit diagram illustrating a twenty-fifthpreferred embodiment of the present invention.

FIG. 50 is a perspective view illustrating the power supply circuitboard of the twenty-fifth preferred embodiment of the present invention.

FIG. 51 is an equivalent circuit diagram illustrating a twenty-sixthpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 52 is a perspective view illustrating the power supply circuitboard of the twenty-sixth preferred embodiment of the present invention.

FIG. 53 is an equivalent circuit diagram illustrating a twenty-seventhpreferred embodiment of the wireless IC device according to the presentinvention.

FIG. 54 is a perspective view illustrating the power supply circuitboard of the twenty-seventh preferred embodiment of the presentinvention.

FIG. 55 is a cross-sectional view illustrating a twenty-eighth preferredembodiment of the wireless IC device according to the present invention.

FIG. 56 is a cross-sectional view illustrating a twenty-ninth preferredembodiment of the wireless IC device according to the present invention.

FIG. 57 is a perspective view illustrating a thirtieth preferredembodiment of the wireless IC device according to the present invention.

FIG. 58 is a perspective view illustrating a thirty-first preferredembodiment of the wireless IC device according to the present invention.

FIG. 59 is a plan view illustrating a first example of a conventionalwireless IC device.

FIG. 60 is a plan view illustrating a second example of a conventionalwireless IC device.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Description will be made below regarding preferred embodiments of thewireless IC device according to the present invention with reference tothe drawings. Note that the common parts and portions of each of thepreferred embodiments described below are denoted with the samereference numerals, and redundant description thereof will be omitted.

First Preferred Embodiment

A wireless IC device 1 a according to the first preferred embodiment isa monopole type, as illustrated in FIG. 1 and FIG. 2, and includes awireless IC chip 5, a power supply circuit board 10 mounted on thewireless IC chip 5, and a radiation pattern 20 bonding the power supplycircuit board 10. The wireless IC chip 5 includes a clock circuit, alogic circuit, and a memory circuit, stores necessary informationtherein, and is subjected to direct DC connection with a power supplycircuit 16 provided in the power supply circuit board 10.

The power supply circuit 16 is a circuit for supplying a transmissionsignal having a predetermined frequency to the radiation pattern 20,and/or a circuit for selecting a reception signal having a predeterminedfrequency from signals received at the radiation pattern 20, andsupplying it to the wireless IC chip 5, and includes a resonant circuitfor resonating with the frequency of a transmission/reception signal.

As illustrated in FIG. 2 and FIG. 3, the power supply circuit board 10includes the power supply circuit 16 built therein defined by aconcentrated-constant-type LC series resonant circuit including ahelical-type inductor device L and capacitance devices C1 and C2.Specifically, as illustrated in FIG. 4, the power supply circuit board10 is obtained by layering, pressure-bonding, and sintering ceramicsheets 11A through 11G each having a dielectric member, and includes thesheet 11A forming electrodes for connection 12, and via hole conductors13 a, the sheet 11B forming capacitance electrodes 14 a, the sheet 11Cforming capacitor electrodes 14 b and via hole conductors 13 b, thesheet 11D forming via hole conductors 13 c, the sheet 11E formingconductor patterns 15 a and via hole conductors 13 d, the sheet 11Fforming via hole conductors 13 e (one sheet or multiple sheets), and thesheet 11G forming conductor patterns 15 b. Note that each of the ceramicsheets 11A through 11G may be a sheet made of a magnetic ceramicmaterial, and the power supply circuit board 10 can be easily obtainedusing a multilayer board manufacturing process, such as a sheet layeringmethod, a thick-film printing method, or the like, which have beenconventionally used.

The sheets 11A through 11G are layered, thereby forming the inductancedevice L of which a helical winding axis is substantially parallel tothe radiation pattern 20, and the capacitance devices C1 and C2 whereinthe capacitor electrodes 14 b are connected to both ends of theinductance device L, and the capacitor electrodes 14 a are connected tothe electrodes for connection 12 via the via hole conductors 13 a. Theelectrodes for connection 12, which are board-side electrode patterns,are connected to the chip-side electrode pattern (not shown) of thewireless IC chip 5 via a soldering bump 6 using DC connection.

That is to say, of the devices of the power supply circuit 16, atransmission signal is fed from the inductance device L which is acoil-shaped electrode pattern to the radiation pattern 20 via magneticfiled, and also a reception signal from the radiation pattern 20 is fedto the inductance device L via magnetic field. Therefore, with the powersupply circuit board 10, in the inductance device L and the capacitancedevices C1 and C2, which make up the resonant circuit, it is preferablethat the inductance device L is disposed so as to be closer to theradiation pattern 20.

The radiation pattern 20 is a long member made of a nonmagnetic membersuch as aluminum foil, copper foil, or other suitable member, i.e., aboth-end-open-type metal member, and is formed on an insulating flexibleresin film 21, such as PET or other suitable resin film. With the powersupply circuit board 10, the lower side thereof is adhered to theradiation pattern 20 via an insulating adhesive layer made of anadhesive agent 18.

To show one example from the perspective of sizes, the thickness of thewireless IC chip 5 is about 50 μm to about 100 μm, the thickness of thesoldering bump 6 is about 20 μm, the thickness of the power supplycircuit board 10 is about 200 μm to about 500 μm, the thickness of theadhesive agent 18 is about 0.1 μm to about 10 μm, the thickness of theradiation pattern 20 is about 1 μm to about 50 μm, and the thickness ofthe film 21 is about 10 μm to about 100 μm. Also, the area of thewireless IC chip 5 can be varied, such as 0.4 mm×0.4 mm, 0.9 mm×0.8 mm,and so forth. The area of the power supply circuit board 10 can be fromapproximately the same size as the wireless IC chip 5 to about 3 mm×3mm.

FIGS. 5A and 5B illustrate connection arrangements between the wirelessIC chip 5 and the power supply circuit board 10. FIG. 5A illustrates aconnection arrangement wherein one pair of antenna (balance) terminals 7a and 17 a are provided on the rear side of the wireless IC chip 5 andthe front side of the power supply circuit board 10 respectively. FIG.5B illustrates another connection arrangement wherein ground terminals 7b and 17 b are provided at the rear side of the wireless IC chip 5 andthe front side of the power supply circuit board 10, respectively, inaddition to the pair of antenna (balance) terminals 7 a and 17 a.However, the ground terminals 17 b of the power supply circuit board 10are terminated, and are not connected to another device of the powersupply circuit board 10.

Also, as illustrated in FIG. 6 and FIG. 7, it is preferable that theradiation pattern 20 has a slender shape, and the area of a portion 20′to which the power supply circuit board 10 is adhered is greater thanthe board 10. It is not necessary to determine precise positionalaccuracy at the time of adhesion, and stable electric properties can beobtained.

FIG. 3 illustrates the equivalent circuit of the wireless IC chip device1 a. With this wireless IC device 1 a, a high-frequency signal (e.g.,UHF frequency band) radiated from the unshown reader/writer is receivedat the radiation pattern 20, the power supply circuit 16 (the LC seriesresonant circuit including the inductance device L and the capacitancedevices C1 and C2) that is primarily magnetically-coupled with theradiation pattern 20 is resonated, and only the reception signal havinga predetermined frequency band is supplied to the wireless IC chip 5. Onthe other hand, predetermined energy is extracted from this receptionsignal, the information stored in the wireless IC chip 5 is received asan input signal, and reflection modulation is performed on this inputsignal with that energy as a driving source to obtain a transmissionsignal, and the transmission signal is subjected to matching with apredetermined frequency at the power supply circuit 16, following thetransmission signal is propagated from the inductance device L of thepower supply circuit 16 to the radiation pattern 20 via magneticcoupling, and is transmitted and transferred from the radiation pattern20 to the reader/writer.

Note that coupling between the power supply circuit 16 and the radiationpattern 20 is primarily coupling via magnetic field, but coupling viaelectric field may be provided (electromagnetic coupling).

With the wireless IC device 1 a according to the first preferredembodiment, the wireless IC chip 5 is directly DC-connected on the powersupply circuit board 10 including the power supply circuit 16, the powersupply circuit board 10 has substantially the same area as the wirelessIC chip 5, and is rigid, so the wireless IC chip 5 can be preciselypositioned and mounted thereupon as compared to mounting it on aflexible film having a wide area in the conventional manner. Moreover,the power supply circuit board 10 is preferably made of a ceramicmaterial, and has thermal resistance, whereby the wireless IC chip 5 canbe soldered to the power supply circuit board 10. That is to say, anexpensive ultrasonic bonding method as is conventional is not used, andthere is no danger that the wireless IC chip 5 is damaged with pressureapplied during ultrasonic bonding. Instead, a self alignment operationusing a soldering flow can be used.

With the power supply circuit 16, resonant frequency properties aredetermined by the resonant circuit including the inductance device L andthe capacitance devices C1 and C2. The resonant frequency of the signalradiated from the radiation pattern 20 is substantially equivalent tothe self resonant frequency of the power supply circuit 16, and themaximum gain of the signal is substantially determined by at least oneof the size and shape of the power supply circuit 16, and the distanceand medium between the power supply circuit 16 and the radiation pattern20. Specifically, with the first preferred embodiment, the electriclength of the radiation pattern 20 is set to approximately half of aresonant frequency λ. However, the electric length of the radiationpattern 20 may not be an integer multiple of λ/2. That is to say, withthe present invention, the frequency of the signal radiated from theradiation pattern 20 is substantially determined by the resonantfrequency of the resonant circuit (power supply circuit 16). Thus,frequency properties are not substantially dependent on the electriclength of the radiation pattern 20. It is preferable that the electriclength of the radiation pattern 20 be an integer multiple of λ/2 so asto maximize gain.

As described above, the resonant frequency properties of the powersupply circuit 16 are determined by the resonant circuit including theinductance device L and the capacitance devices C1 and C2, which aredisposed in the power supply circuit board 10, so the resonant frequencyproperties are not varied even if the wireless IC device 1 a is insertedin a book. Also, the resonant frequency properties are not varied evenif the wireless IC device 1 a is rounded to change the shape of theradiation pattern 20, or the size of the radiation pattern 20 ischanged. Also, with a coil-shaped electrode pattern defining theinductance device L, the winding axis thereof is substantially parallelto the radiation pattern 20, such that the center frequency is notvaried. Also, the capacitance devices C1 and C2 are inserted downstreamof the wireless IC chip 5, such that a low-frequency surge is preventedwith these devices C1 and C2, and the wireless IC chip 5 is protectedfrom a surge.

Further, the power supply circuit board 10 is a rigid multilayer board,so that it is easy to handle when soldering the wireless IC chip 5.Moreover, the radiation pattern 20 is made of a flexible metal filmsupported by the flexible film 21, so as to be easily adhered to acylindrical member, for example, such as a plastic-film flexible bag orplastic bottle without any obstructions.

Note that with the present invention, the resonant circuit may alsofunction as a matching circuit for performing matching between theimpedance of the wireless IC chip and the impedance of the radiationpattern. Alternatively, the power supply circuit board may furtherinclude a matching circuit provided separately from the resonant circuitincluding the inductance device and the capacitance devices. When addingthe function of the matching circuit to the resonant circuit, design ofthe resonant circuit is complex. By providing the matching circuitseparately from the resonant circuit, the resonant circuit and thematching circuit can be independently designed.

Second Preferred Embodiment

A wireless IC device 1 b according to a second preferred embodiment isobtained by branching the radiation pattern 20 ninety degrees as shownin FIG. 8. That is to say, the radiation pattern 20 includes a radiationportion 20 a extending in the X-axis direction within an x-y plane, anda radiation portion 20 b extending in the Y-axis direction, a portionabove the extension of the radiation portion 20 a defines a power supplyportion 20 d, and the power supply circuit board 10, on which thewireless IC chip 5 is mounted, is adhered to the power supply portion 20d.

Note that the internal configuration of the power supply circuit board10 is preferably the same as that in the first preferred embodiment, andthe operations and advantages of the present second preferred embodimentare substantially the same as those in the first preferred embodiment.Further, the radiation portions 20 a and 20 b extend in the X-axisdirection and Y-axis direction, whereby circularly-polarized waves arereceived, and antenna gain is improved.

Third Preferred Embodiment

With a wireless IC device 1 c according to a third preferred embodiment,as illustrated in FIGS. 9A and 9B, the radiation pattern 20 includesradiation portions 20 a, 20 b, and 20 c extending in the X-axisdirection, Y-axis direction, and Z-axis direction in x-y-z space, aportion above the extension of the radiation portion 20 a defines apower supply portion 20 d, and the power supply circuit board 10, onwhich the wireless IC chip 5 is mounted, is adhered to the power supplyportion 20 d.

The radiation pattern 20 of this wireless IC device 1 c is adhered to acorner portion of a box-shaped article, the radiation portions 20 a, 20b, and 20 c extending three-dimensionally, so the directivity of theantenna is eliminated, and consequently, effectivetransmission/reception can be performed in any direction. Further, theother operations and advantages of the wireless IC device 1 c are thesame as those in the first preferred embodiment.

Fourth Preferred Embodiment

With a wireless IC device 1 d according to a fourth preferredembodiment, as illustrated in FIG. 10, the radiation pattern 20 having awide area and made of aluminum foil or other suitable material isdisposed on a plastic film 21 having a wide area and flexibleinsulation, and the power supply circuit board 10, on which the wirelessIC chip 5 is mounted, is adhered to an arbitrary portion of theradiation pattern 20.

Note that other configurations of the wireless IC device 1 d, i.e., theinternal configurations of the power supply circuit board 10 are thesame as that in the first preferred embodiment. Accordingly, theoperations and advantages of the present fourth preferred embodiment aresubstantially the same as those in the first preferred embodiment, andthe present fourth preferred embodiment further includes an advantagewherein minimal accuracy regarding the adhesive position of the powersupply circuit board 10 is required.

Fifth Preferred Embodiment

With a wireless IC device 1 e according to a fifth preferred embodiment,as illustrated in FIG. 11, the radiation pattern 20 having a wide areaand made of aluminum foil or other suitable material is preferablyconfigured in a mesh shape. The mesh may be formed on the entire surfaceof the radiation pattern 20, or may be formed partially.

The other configurations are preferably the same as those in the fourthpreferred embodiment, in addition to an advantage wherein high accuracyis not required regarding the adhesive position of the power supplycircuit board 10, the magnetic flux of the coil-shaped electrode patternis passing through opening portions, so variations of magnetic fluxgenerated from the power supply circuit board 10 is reduced, many moremagnetic fluxes can be passed through the radiation pattern 20.Accordingly, the propagation efficiency of signal energy is improved,and a frequency shift due to bonding is reduced.

Sixth Preferred Embodiment

With a wireless IC device 1 f according to a sixth preferred embodiment,as illustrated in FIG. 12, an adhesive agent 18 is applied to thesurface other than the bonding surface bonded to the power supplycircuit board 10 (here, entire surface) on a film 21 via the radiationpattern 20. This adhesive agent 18 enables the wireless IC device if tobe adhered to an arbitrary portion of an article.

Note that other configurations of the wireless IC device 1 f, i.e., theinternal configurations of the power supply circuit board 10 aresubstantially the same as those in the first preferred embodiment.Accordingly, the operations and advantages of the present sixthpreferred embodiment are substantially the same as those in the firstpreferred embodiment.

Seventh Preferred Embodiment

With a wireless IC device 1 g according to a seventh preferredembodiment, as illustrated in FIG. 13 as an equivalent circuit, theinductance device L including a coil-shaped electrode pattern definingthe power supply circuit 16 is disposed in the power supply circuitboard 10. A capacitance device C defining a LC parallel resonant circuitis configured as a floating capacitance (distributed-constant-typecapacitance) between the conductor patterns of the inductance device L.

That is to say, when even one coil-shaped electrode pattern has a selfresonance, the L component of the coil-shaped electrode pattern itselfand the C component which is a line floating capacitance function as anLC parallel resonant circuit, thereby functioning the power supplycircuit 16. Accordingly, with this wireless IC device 1 g, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC parallel resonant circuit including theinductance device L and the capacitance device C) that is primarilymagnetically-coupled with the radiation pattern 20 is resonated, andonly the reception signal having a predetermined frequency band issupplied to the wireless IC chip 5. On the other hand, predeterminedenergy is extracted from the reception signal, the information stored inthe wireless IC chip 5 provided as an input signal, and reflectionmodulation is provided as the input signal with that energy as a drivingsource to obtain a transmission signal, and the transmission signal ismatched with a predetermined frequency at the power supply circuit 16,following the transmission signal is propagated from the inductancedevice L of the power supply circuit 16 to the radiation pattern 20 viamagnetic coupling, and is transmitted and transferred from the radiationpattern 20 to the reader/writer.

Eighth Preferred Embodiment

A wireless IC device 1 h according to an eighth preferred embodiment, asillustrated in FIG. 14 as an equivalent circuit, includes a dipole-typepower supply circuit 16, and the radiation pattern 20. The power supplycircuit 16 includes two LC parallel resonant circuits disposed in apower supply circuit board. An inductance device L1 and a capacitancedevice C1 are connected to a first port side of the wireless IC chip 5,and an inductance device L2 and a capacitance device C2 are connected toa second port side of the wireless IC chip 5, each facing the radiationpatterns 20 and 20. The end portions of the inductance device L1 and thecapacitance device C1 are set to open ends. Note that a first port and asecond port define the I/O ports of a difference circuit.

The operations and advantages of the present eighth preferred embodimentare substantially the same as those in the first preferred embodiment.That is to say, with this wireless IC device 1 h, a high-frequencysignal (e.g., UHF frequency band) radiated from the unshownreader/writer is received at the radiation pattern 20, the power supplycircuit 16 (the LC parallel resonant circuit including the inductancedevice L1 and the capacitance device C1, and the LC parallel resonantcircuit including of the inductance device L2 and the capacitance deviceC2) that are primarily magnetically-coupled with the radiation pattern20 is resonated, and only the reception signal having a predeterminedfrequency band is supplied to the wireless IC chip 5. On the other hand,predetermined energy is extracted from this reception signal, theinformation stored in the wireless IC chip 5 is provided an inputsignal, and reflection modulation is provided as the input signal withthat energy as a driving source to obtain a transmission signal, and thetransmission signal is matched with a predetermined frequency at thepower supply circuit 16, following the transmission signal is propagatedfrom the inductance devices L1 and L2 of the power supply circuit 16 tothe radiation pattern 20 via magnetic coupling, and is transmitted andtransferred from the radiation pattern 20 to the reader/writer.

Ninth Preferred Embodiment

A wireless IC device 1 i according to a ninth preferred embodiment, asillustrated in FIG. 15 as an equivalent circuit, is a device including adipole-type power supply circuit 16, and the radiation pattern 20. Thepower supply circuit 16 includes two LC series resonant circuitsdisposed in a power supply circuit board. Respective inductance devicesL1 and L2 face the radiation patterns 20 and 20, and respectivecapacitance devices C1 and C2 are connected to ground.

The operations and advantages of the present ninth preferred embodimentare substantially the same as those in the first preferred embodiment.That is to say, with this wireless IC device 1 i, a high-frequencysignal (e.g., UHF frequency band) radiated from the unshownreader/writer is received at the radiation pattern 20, the power supplycircuit 16 (the LC series resonant circuit including the inductancedevice L1 and the capacitance device C1, and the LC series resonantcircuit including the inductance device L2 and the capacitance deviceC2) that are primarily magnetically-coupled with the radiation pattern20 is resonated, and only the reception signal having a predeterminedfrequency band is supplied to the wireless IC chip 5. On the other hand,predetermined energy is extracted from this reception signal, theinformation stored in the wireless IC chip 5 is provided as an inputsignal, and reflection modulation is applied to the input signal withthat energy as a driving source to obtain a transmission signal, and thetransmission signal is matched with a predetermined frequency at thepower supply circuit 16, following the transmission signal is propagatedfrom the inductance devices L1 and L2 of the power supply circuit 16 tothe radiation pattern 20 via magnetic coupling, and is transmitted andtransferred from the radiation pattern 20 to the reader/writer.

Tenth Preferred Embodiment

A wireless IC device 1 j according to a tenth preferred embodiment, asillustrated in FIG. 16, is a monopole type, wherein an inductance deviceL and a capacitance device C disposed in the power supply circuit board10 define the power supply circuit 16 as an LC series resonant circuit.As illustrated in FIG. 17, with a coil-shaped electrode pattern definingthe inductance device L, the winding axis thereof is substantiallyperpendicular to the radiation portion 20, and the power supply circuit16 is principally magnetically-coupled with the radiation portion 20.

The power supply circuit board 10 is, specifically, as illustrated inFIG. 18, preferably obtained by layering, pressure-bonding, andsintering ceramic sheets 31A through 31F each made up of a dielectricmember, and includes the sheet 31A forming electrodes for connection 32and via hole conductors 33 a, the sheet 31B forming a capacitanceelectrode 34 a and a via hole conductor 33 b, the sheet 31C forming acapacitor electrode 34 b and via hole conductors 33 c and 33 b, thesheet 31D (one sheet or multiple sheets) forming a conductor pattern 35a and via hole conductors 33 d and 33 b, the sheet 31E (one sheet ormultiple sheets) forming a conductor pattern 35 b and via holeconductors 33 e and 33 b, and the sheet 31F forming a conductor pattern35 c.

The above-described sheets 31A through 31F are layered, therebyobtaining the power supply circuit 16 defined by an LC series resonantcircuit wherein the capacitance device C is serially connected to theinductance device L of which a helical winding axis is substantiallyperpendicular to the radiation pattern 20. The capacitance electrode 34a is connected to the electrode for connection 32 via the via holeconductor 33 a, and further connected to the wireless IC chip 5 via thesoldering bump 6. One end of the inductance device L is connected to theelectrode for connection 32 via the via hole conductor 33 b, and furtherconnected to the wireless IC chip 5 via the soldering bump 6.

The operations and advantages of the present tenth preferred embodimentare substantially the same as those in the first preferred embodiment.That is to say, with this wireless IC device 1 j, a high-frequencysignal (e.g., UHF frequency band) radiated from the unshownreader/writer is received at the radiation pattern 20, the power supplycircuit 16 (the LC series resonant circuit including the inductancedevice L and the capacitance device C) that is primarilymagnetically-coupled with the radiation pattern 20 is resonated, andonly the reception signal having a predetermined frequency band issupplied to the wireless IC chip 5. On the other hand, predeterminedenergy is extracted from this reception signal, the information storedin the wireless IC chip 5 is provided as an input signal, and reflectionmodulation is applied to this input signal with the energy as a drivingsource to obtain a transmission signal, and the transmission signal ismatched with a predetermined frequency at the power supply circuit 16,following which the transmission signal is propagated from theinductance device L of the power supply circuit 16 to the radiationpattern 20 via magnetic coupling, and is transmitted and transferredfrom the radiation pattern 20 to the reader/writer.

Particularly, according to the present tenth preferred embodiment, withthe coil-shaped electrode pattern, the winding axis thereof issubstantially perpendicular to the radiation pattern 20, andaccordingly, the present tenth preferred embodiment achieves advantageswherein the magnetic flux component increases as to the radiationpattern 20, propagation efficiency of signal energy improves, and gainalso increases.

Eleventh Preferred Embodiment

With a wireless IC device 1 k according to an eleventh preferredembodiment, as illustrated in FIG. 19 as an equivalent circuit, thewinding width (coil diameter) of the coil-shaped electrode pattern ofthe inductance device L illustrated in the tenth preferred embodimentgradually increases toward the radiation pattern 20. The otherconfigurations are substantially the same as those in the tenthpreferred embodiment.

The present eleventh preferred embodiment has the same operations andadvantages as those in the tenth preferred embodiment, and additionally,the winding width (coil diameter) of the coil-shaped electrode patternof the inductance device L gradually increases toward the radiationpattern 20, thereby improving the propagation efficiency of signals.

Twelfth Preferred Embodiment

A wireless IC device 1 l according to a twelfth preferred embodiment, asillustrated in FIG. 20 as an equivalent circuit, is a dipole type,wherein the power supply circuit 16 includes two LC series resonantcircuits disposed in the power supply circuit board 10.

Specifically, the power supply circuit board 10 is, as illustrated inFIG. 21, obtained by layering, pressure-bonding, and sintering ceramicsheets 41A through 41F each made of a dielectric member, and includesthe sheet 41A forming electrodes for connection 42 and via holeconductors 43 a, the sheet 41B forming capacitance electrodes 44 a, thesheet 41C forming capacitor electrodes 44 b and via hole conductors 43b, the sheet 41D (one sheet or multiple sheets) forming conductorpatterns 45 a and via hole conductors 43 c, the sheet 41E (one sheet ormultiple sheets) forming conductor patterns 45 b and via hole conductors43 d, and the sheet 41F forming conductor patterns 45 c.

The above-described sheets 41A through 41F are layered, therebyobtaining the power supply circuit 16 including the two LC seriesresonant circuits wherein the capacitance devices C1 and C2 are seriallyconnected to the inductance devices L1 and L2 of which helical windingaxes are substantially perpendicular to the radiation pattern 20. Thecapacitance electrodes 44 a are connected to the electrodes forconnection 42 via the via hole conductors 43 a, and further connected tothe wireless IC chip 5 via a soldering bump.

The operations and advantages of the present twelfth preferredembodiment are substantially the same as those in the first preferredembodiment. That is to say, with this wireless IC device 1 l, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit including theinductance device L1 and the capacitance device C1, and the LC seriesresonant circuit including the inductance device L2 and the capacitancedevice C2) that are primarily magnetically-coupled with the radiationpattern 20 is resonated, and only the reception signal having apredetermined frequency band is supplied to the wireless IC chip 5. Onthe other hand, predetermined energy is extracted from this receptionsignal, the information stored in the wireless IC chip 5 is provided asan input signal, and reflection modulation is applied to this inputsignal with that energy as a driving source to obtain a transmissionsignal, and the transmission signal is matched with a predeterminedfrequency at the power supply circuit 16, following the transmissionsignal is propagated from the inductance devices L1 and L2 of the powersupply circuit 16 to the radiation pattern 20 via magnetic coupling, andis transmitted and transferred from the radiation pattern 20 to thereader/writer.

Also, the capacitance devices C1 and C2 are disposed downstream of theIC chip 5 and between the IC chip 5 and the inductance devices L1 andL2, so as to improve surge resistance. A surge is a low-frequencycurrent up to about 200 MHz, which can be removed by the capacitancedevices C1 and C2, and the surge breakdown of the wireless IC chip 5 isprevented.

Note that with the present twelfth preferred embodiment, the resonantcircuit including the capacitance device C1 and the inductance device L1and the resonant circuit including the capacitance device C2 and theinductance device L2 are not coupled mutually.

Thirteenth Preferred Embodiment

A wireless IC device 1 m according to a thirteenth preferred embodimentis, as illustrated in FIG. 22, a device wherein the surface of a rigidsingle-layer power supply circuit board 50 made of a ceramic orheat-resistance resin is provided with a power supply circuit 56 definedby a coil-shaped electrode pattern, i.e., a spiral-type inductancedevice, provided on the surface thereof. Both end portions of the powersupply circuit 56 are directly connected to the wireless IC chip 5 via asoldering bump, and the power supply circuit board 50 is adhered to thefilm 21 on which the radiation pattern 20 is provided using an adhesiveagent. Also, a conductor pattern 56 a and conductors 56 b and 56 c whichdefine the power supply circuit 56, and mutually cross are isolated byan unshown insulating film.

The power supply circuit 56 according to the present thirteenthpreferred embodiment defines an LC parallel resonant circuit wherein afloating capacitance provided between conductor patterns wound in aspiral manner is used as a capacitance component. Also, the power supplycircuit board 50 is a single-layer board made of a dielectric member ormagnetic member.

With the wireless IC device 1 m according to the present preferredthirteenth embodiment, the power supply circuit 56 is primarilymagnetically coupled with the radiation pattern 20. Accordingly, as withthe above-described preferred embodiments, a high-frequency signalradiated from the reader/writer is received at the radiation pattern 20,the power supply circuit 56 is resonated, only the reception signalhaving a predetermined frequency band is supplied to the wireless ICchip 5. On the other hand, predetermined energy is extracted from thisreception signal, the information stored in the wireless IC chip 5 isprovided as an input signal, and reflection modulation is applied tothis input signal with that energy as a driving source to obtain atransmission signal, and the transmission signal is matched with apredetermined frequency at the power supply circuit 56, following thetransmission signal is propagated from the inductance device of thepower supply circuit 56 to the radiation pattern 20 via magneticcoupling, and is transmitted and transferred from the radiation pattern20 to the reader/writer.

As with the first preferred embodiment in that the wireless IC chip 5 isprovided on the rigid power supply circuit board 50 having a small area,positioning accuracy is excellent, so the wireless IC chip 5 can beconnected to the power supply circuit board 50 using a soldering bump.

Fourteenth Preferred Embodiment

With a wireless IC device 1 n according to a fourteenth preferredembodiment, as illustrated in FIG. 23, the coil-shaped electrode patternof the power supply circuit 56 is provided in the power supply circuitboard 50. The power supply circuit board 50 is, as illustrated in FIG.24, obtained by layering, pressure-bonding, and sintering ceramic sheets51A through 51D each made of a dielectric member, and includes the sheet51A forming electrodes for connection 52 and via hole conductors 53 a,the sheet 51B forming a conductor pattern 54 a and via hole conductors53 b and 53 c, the sheet 51C forming a conductor pattern 54 b, and theplain sheet 51D (multiple sheets).

The sheets 51A through 51D are layered, thereby obtaining the powersupply circuit board 50 which includes the power supply circuit 56including a resonant circuit defined by the inductance device wound in aspiral shape, and the capacitance component defined by a floatingcapacitance between lines of the spiral-shaped conductor in thecoil-shaped electrode pattern. The electrodes for connection 52positioned on both ends of the power supply circuit 56 are connected tothe wireless IC chip 5 via a soldering bump 6. The operations andadvantages of the present fourteenth preferred embodiment aresubstantially the same as those in the thirteenth preferred embodiment.

Fifteenth Preferred Embodiment

A wireless IC device 10 according to a fifteenth preferred embodimentis, as illustrated in FIG. 25 as an equivalent circuit, a device whichis subjected to capacitive coupling between the wireless IC chip 5 andthe power supply circuit board 10, and the power supply circuit board 10and the radiation pattern 20 are connected by DC connection. The powersupply circuit board 10 includes the power supply circuit 16 made up oftwo LC series resonant circuits disposed therein. With the inductancedevices L1 and L2, the winding axes thereof are positioned substantiallyperpendicular to the radiation pattern 20, and one of the ends thereofis connected to capacitor electrodes 65 a and 65 b (see FIG. 26)defining the capacitance devices C1 and C2, and the other ends thereofare mutually direct-connected by an electrode for connection 62 providedon the bottom surface of the board 10. Also, capacitor electrodes 66 aand 66 b (see FIG. 26) defining the capacitance devices C1 and C2 areprovided on the rear side of the wireless IC chip 5.

Specifically, the power supply circuit board 10 is, as illustrated inFIG. 26, obtained by layering, pressure-bonding, and sintering ceramicsheets 61A through 61G each made up of a dielectric member, and includesthe sheet 61A forming an electrode for connection 62 and via holeconductors 63 a and 63 b, the sheets 61B through 61F forming conductorpatterns 64 a and 64 b and via hole conductors 63 c and 63 d, and thesheet 61G forming capacitor electrodes 65 a and 65 b.

The above-described sheets 61A through 61G are layered, therebyobtaining the power supply circuit 16 including the two LC seriesresonant circuits wherein the capacitance devices C1 and C2 are seriallyconnected to the inductance devices L1 and L2.

That is to say, the capacitance device C1 is defined between the planeelectrode patterns of the electrode 66 a functioning as a chip-sideelectrode pattern and the electrode 65 a functioning as a board-sideelectrode pattern which are mutually parallel. The capacitance device C2is provided between the plane electrode patterns of the electrode 66 bfunctioning as a chip-side electrode pattern and the electrode 65 bfunctioning as a board-side electrode pattern which are substantiallymutually parallel. The wireless IC chip 5 is adhered to the power supplycircuit board 10 using an insulating adhesive layer, and is connected tothe power supply circuit board 10 via this insulating adhesive layer.Also, the power supply circuit board 10 is DC-connected to the radiationpattern 20 via the electrode for connection 62 functioning as asecond-board-side electrode pattern. Here, between the electrode forconnection 62 of the power supply circuit board 10 and the radiationpattern 20 may be connected using soldering, an electroconductiveadhesive agent, or other suitable agent.

The operations and advantages of the present fifteenth embodiment arebasically the same as those in the first preferred embodiment. That isto say, with this wireless IC device 10, a high-frequency signal (e.g.,UHF frequency band) radiated from the unshown reader/writer is receivedat the radiation pattern 20, the power supply circuit 16 (the LC seriesresonant circuit including the inductance device L1 and the capacitancedevice C1, and the LC series resonant circuit including the inductancedevice L2 and the capacitance device C2) DC-connected to the radiationpattern 20 is resonated, and only the reception signal having apredetermined frequency band is supplied to the wireless IC chip 5. Onthe other hand, predetermined energy is extracted from this receptionsignal, the information stored in the wireless IC chip 5 is provided asan input signal, and reflection modulation is applied to this inputsignal with that energy as a driving source to obtain a transmissionsignal, and the transmission signal is matched with a predeterminedfrequency at the power supply circuit 16, following the transmissionsignal is propagated to the radiation pattern 20 DC-connected to thepower supply circuit 16, and is transmitted and transferred from theradiation pattern 20 to the reader/writer. The power supply circuit 16and the wireless IC chip 5 are subjected to capacitive coupling by thecapacitance devices C1 and C2, whereby electric power and atransmission/reception signal are transmitted therebetween.

Incidentally, the areas of the capacitor electrodes 65 a and 65 bprovided on the power supply circuit board 10 are configured so as to begreater than the areas of the capacitor electrodes 66 a and 66 bprovided on the wireless IC chip 5. Accordingly, even if the positionalaccuracy somewhat varies at the time of mounting the wireless IC chip 5on the power supply circuit board 10, variations of capacitance providedbetween the capacitor electrodes 65 a, 66 a and 65 b, 66 b areprevented. Also, the capacitance devices C1 and C2 are inserteddownstream of the wireless IC chip 5, whereby surge-resistancecapabilities improve.

Sixteenth Preferred Embodiment

A wireless IC device 1 p according to a sixteenth preferred embodimentincludes, as illustrated in FIG. 27 as an equivalent circuit, capacitivecoupling between the power supply circuit board 10 and the radiationpattern 20. The power supply circuit board 10 includes the power supplycircuit 16 defined by two LC series resonant circuits. One of the endsof the inductance devices L1 and L2 is connected to the wireless IC chip5, and the other ends thereof are connected to capacitor electrodes 72 aand 72 b (see FIG. 28) defining the capacitance devices C1 and C2provided on the front side of the board 10. Also, the end portions 20 aand 20 b of the radiation pattern 20 functions as another capacitorelectrode defining the capacitance devices C1 and C2.

Specifically, the power supply circuit board 10 is, as illustrated inFIG. 28, obtained by layering, pressure-bonding, and sintering ceramicsheets 71A through 71F each made of a dielectric member, and includesthe sheet 71A forming capacitor electrodes 72 a and 72 b and via holeconductors 73 a and 73 b, the sheets 71B through 71E forming conductorpatterns 74 a and 74 b and via hole conductors 73 c and 73 d, and thesheet 71F wherein conductor patterns 74 a and 74 b are formed on oneside, electrodes for connection 75 a and 75 b are formed on the otherside, and both are connected with via hole conductors 73 e and 73 f.

The sheets 71A through 71F are layered, thereby obtaining the powersupply circuit 16 including the two LC series resonant circuits whereinthe capacitance devices C1 and C2 are serially connected to theinductance devices L1 and L2. The power supply circuit board 10 isadhered to the radiation pattern 20 using an adhesive agent, whereby thecapacitor electrodes 72 a and 72 b functioning as plane electrodepatterns disposed substantially in parallel to the radiation pattern 20face the end portions 20 a and 20 b of the radiation pattern 20 via theinsulating adhesive layer, and define the capacitance devices C1 and C2.Also, the electrodes for connection 75 a and 75 b are connected to thewireless IC chip 5 via a soldering bump, whereby one of the ends of theinductance devices L1 and L2 is connected to the wireless IC chip 5, andthe wireless IC chip 5 and the power supply circuit board 10 areDC-connected.

Note that when the adhesive agent includes dielectric powder, theadhesive layer consequently includes properties as a dielectric member,whereby the capacitance of the capacitance devices C1 and C2 isincreased. Also, with the sixteenth preferred embodiment, the capacitorelectrodes 72 a and 72 b functioning as the second-board-side electrodepatterns are disposed on the rear-side surface of the power supplycircuit board 10, but may be disposed within the power supply circuitboard 10, preferably on the side near the radiation pattern 20. Also,the capacitor electrodes 72 a and 72 b may be provided in an inner layerof the board 10.

The operations and advantages of the present sixteenth preferredembodiment are substantially the same as those in the first preferredembodiment. That is to say, with this wireless IC device 1 p, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit made up of theinductance device L1 and the capacitance device C1, and the LC seriesresonant circuit made up of the inductance device L2 and the capacitancedevice C2) capacitively-coupled with the radiation pattern 20 isresonated, and only the reception signal having a predeterminedfrequency band is supplied to the wireless IC chip 5. On the other hand,predetermined energy is extracted from this reception signal, theinformation stored in the wireless IC chip 5 is provided as an inputsignal, and reflection modulation is applied to this input signal withthat energy as a driving source to obtain a transmission signal, and thetransmission signal is matched with a predetermined frequency at thepower supply circuit 16, following the transmission signal is propagatedto the radiation pattern 20 via capacitive coupling by the capacitancedevices C1 and C2, and is transmitted and transferred from the radiationpattern 20 to the reader/writer.

Seventeenth Preferred Embodiment

With a wireless IC device 1 q according to a seventeenth preferredembodiment, as illustrated in FIG. 29 as an equivalent circuit, thepower supply circuit 16 includes inductance devices L1 and L2 which aremutually magnetically-coupled, wherein the inductance device L1 isconnected to the wireless IC chip 5 via capacitance devices C1 a and C1b, and connected to the inductance device L2 via capacitance devices C2a and C2 b substantially in parallel. In other words, the power supplycircuit 16 is configured so as to include an LC series resonant circuitdefining the inductance device L1 and the capacitance devices C1 a andC1 b, and an LC series resonant circuit defining the inductance deviceL2 and the capacitance devices C2 a and C2 b, and both resonant circuitsare coupled with magnetic coupling denoted M in FIG. 29. Also, both ofthe inductance devices L1 and L2 are magnetically coupled with theradiation pattern 20.

Specifically, the power supply circuit board 10 is, as illustrated inFIG. 30, obtained by layering, pressure-bonding, and sintering ceramicsheets 81A through 81H each made of a dielectric member, and includesthe plain sheet 81A, the sheet 81B forming conductor patterns 82 a and82 b and via hole conductors 83 a, 83 b, 84 a, and 84 b, the sheet 81Cforming conductor patterns 82 a and 82 b and via hole conductors 83 c,84 c, 83 e, and 84 e, the sheet 81D forming conductor patterns 82 a and82 b and via hole conductors 83 d, 84 d, 83 e, and 84 e, the sheet 81Eforming capacitor electrodes 85 a and 85 b and a via hole conductor 83e, the sheet 81F forming capacitor electrodes 86 a and 86 b, the plainsheet 81G, and the sheet 81H wherein capacitor electrodes 87 a and 87 bare formed on the rear side thereof.

The sheets 81A through 81H are layered, whereby the conductor patterns82 a are connected via the via hole conductors 83 b and 83 c to definethe inductance device L1, and the conductor patterns 82 b are connectedvia the via hole conductors 84 b and 84 c to define the inductancedevice L2. The capacitor electrodes 86 a and 87 a define the capacitancedevice C1 a, and the capacitor electrode 86 a is connected to one end ofthe inductance device L1 via the via hole conductors 83 e. The capacitorelectrodes 86 b and 87 b define the capacitance device C1 b, and thecapacitor electrode 86 b is connected to the other end of the inductancedevice L1 via the via hole conductor 83 d. Further, the capacitorelectrodes 85 a and 86 a define the capacitance device C2 a, and thecapacitor electrode 85 a is connected to one end of the inductancedevice L2 via the via hole conductors 84 e. The capacitor electrodes 85b and 86 b define the capacitance device C2 b, and the capacitorelectrode 85 b is connected to the other end of the inductance device L2via the via hole conductor 84 d.

The operations and advantages of the present seventeenth preferredembodiment are substantially the same as those in the first preferredembodiment. That is to say, with this wireless IC device 1 q, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit defined by theinductance device L1 and the capacitance devices C1 a and C1 b, and theLC series resonant circuit defined by the inductance device L2 and thecapacitance devices C2 a and C2 b) principally magnetically-coupled withthe radiation pattern 20 is resonated, and only the reception signalhaving a predetermined frequency band is supplied to the wireless ICchip 5. On the other hand, predetermined energy is extracted from thisreception signal, the information stored in the wireless IC chip 5 isprovided as an input signal, and reflection modulation is applied tothis input signal with that energy as a driving source to obtain atransmission signal, and the transmission signal is matched with apredetermined frequency at the power supply circuit 16, following thetransmission signal is propagated to the radiation pattern 20 from theinductance devices L1 and L2 of the power supply circuit 16 via magneticcoupling, and is transmitted and transferred from the radiation pattern20 to the reader/writer.

Particularly, with the present seventeenth preferred embodiment, asillustrated in FIG. 31, a bandwidth X (bandwidth of about −5 dB) inreflection properties achieves a very wide frequency band not less thanabout 150 MHz. This is because the power supply circuit 16 includes themultiple LC resonant circuits including the inductance devices L1 and L2which are mutually magnetically-coupled with high degree of coupling.Also, the capacitance devices C1 a and C1 b are inserted downstream ofthe wireless IC chip 5, thereby improving surge-resistance capabilities.

Eighteenth Preferred Embodiment

With a wireless IC device 1 r according to an eighteenth preferredembodiment, as illustrated in FIG. 32 as an equivalent circuit, thepower supply circuit 16 includes inductance devices L1 and L2 which aremutually magnetically-coupled with high degree of coupling. Theinductance device L1 is magnetically-coupled with an inductance deviceL5 provided in the wireless IC chip 5, and the inductance device L2defines an LC series resonant circuit along with the capacitance deviceC2. Also, the capacitance device C1 is capacitively-coupled with theradiation portion 20, and another capacitance device C3 is insertedbetween the capacitance devices C1 and C2.

Specifically, the power supply circuit board 10 is, as illustrated inFIG. 33, obtained by layering, pressure-bonding, and sintering ceramicsheets 91A through 91E each made of a dielectric member, and includesthe sheet 91A forming conductor patterns 92 a and 92 b and via holeconductors 93 a, 93 b, 94 a, and 94 b, the sheet 91B forming a capacitorelectrode 95 and via hole conductors 93 c, 93 d, and 94 c, the sheet 91Cforming a capacitor electrode 96 and via hole conductors 93 c and 93 d,the sheet 91D forming a capacitor electrode 97 and a via hole conductor93 c, and the sheet 91E forming a capacitor electrode 98.

These sheets 91A through 91E are layered, whereby the inductance deviceL1 is formed at the conductor pattern 92 a, and the inductance device L2is formed at the conductor pattern 92 b. The capacitance device C1 isformed at the capacitor electrodes 97 and 98, one end of the inductancedevice L1 is connected to the capacitor electrode 98 via the via holeconductors 93 a and 93 c, and the other end thereof is connected to thecapacitor electrode 97 via the via hole conductors 93 b and 93 d. Thecapacitance device C2 is formed at the capacitor electrodes 95 and 96,one end of the inductance device L2 is connected to the capacitorelectrode 96 via the via hole conductors 94 a and 94 c, and the otherend thereof is connected to the capacitor electrode 95 via the via holeconductor 94 b. Further, the capacitor electrodes 96 and 97 define thecapacitance device C3.

Also, as illustrated in FIG. 34, the rear side of the wireless IC chip 5is provided with a coil-shaped electrode pattern 99 functioning as achip-side electrode pattern, and the inductance device L5 is defined bythis coil-shaped electrode pattern 99. Note that the surface of thecoil-shaped electrode pattern 99 is provided with a protective film,such as a resin or other suitable film. Thus, the inductance devices L1and L2 defined by a coil-shaped electrode pattern functioning as aboard-side electrode pattern, and the coil-shaped electrode pattern 99are magnetically-coupled.

The operations and advantages of the present eighteenth preferredembodiment are substantially the same as those in the first preferredembodiment. That is to say, with this wireless IC device 1 r, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit defined by theinductance device L2 and the capacitance device C2) capacitively-coupledand magnetically-coupled with the radiation pattern 20 is resonated, andonly the reception signal having a predetermined frequency band issupplied to the wireless IC chip 5. On the other hand, predeterminedenergy is extracted from this reception signal, the information storedin the wireless IC chip 5 is provided as an input signal, and reflectionmodulation is applied to this input signal with that energy as a drivingsource to obtain a transmission signal, and the transmission signal ismatched with a predetermined frequency at the power supply circuit 16,following the transmission signal is propagated to the radiation pattern20 via capacitive coupling and magnetic coupling, and is transmitted andtransferred from the radiation pattern 20 to the reader/writer. Magneticcoupling is provided between the power supply circuit 16 and thewireless IC chip 5 by the inductance devices L1 and L5, therebytransmitting electric power and a transmission/reception signal.

Nineteenth Preferred Embodiment

With a wireless IC device is according to a nineteenth preferredembodiment, as illustrated in FIG. 35 as an equivalent circuit, thepower supply circuit 16 includes inductance devices L1, L2, and L3 whichare mutually magnetically-coupled with a high degree of coupling. Theinductance device L1 is magnetically-coupled with an inductance deviceL5 provided in the wireless IC chip 5, the inductance device L2 definesan LC series resonant circuit along with the capacitance devices C1 aand C1 b, and the inductance device L3 defines an LC series resonantcircuit along with the capacitance devices C2 a and C2 b. Also, theinductance devices L1, L2, and L3 are each magnetically-coupled with theradiation pattern 20.

Specifically, the power supply circuit board 10 is, as illustrated inFIG. 36, obtained by layering, pressure-bonding, and sintering ceramicsheets 101A through 101E each made of a dielectric member, and includesthe sheet 101A forming a conductor pattern 102 a and via hole conductors103 a and 103 b, the sheet 101B forming capacitor electrodes 104 a and104 b, the sheet 101C forming capacitor electrodes 105 a and 105 b andvia hole conductors 103 c and 103 d, the sheet 101D forming capacitorelectrodes 106 a and 106 b and via hole conductors 103 c, 103 d, 103 e,and 103 f, and the sheet 101E forming conductor patterns 102 b and 102c. That is to say, space is provided between the electrodes 104 a, 105a, and 106 a, and the electrodes 104 b, 105 b, and 106 b, which definethe capacitance device, such that the magnetic flux caused by theinductance device L1 reaches the inductance devices L2, L3 and theradiation pattern 20.

These sheets 101A through 101E are layered, whereby the inductancedevice L1 is formed at the conductor pattern 102 a, the inductancedevice L2 is formed at the conductor pattern 102 b, and the inductancedevice L3 is formed at the conductor pattern 102 c. The capacitancedevice C1 a is formed at the capacitor electrodes 104 a and 105 a, andthe capacitance device C1 b is formed at the capacitor electrodes 104 band 105 b. Also, the capacitance device C2 a is formed at the capacitorelectrodes 105 a and 106 a, and the capacitance device C2 b is formed atthe capacitor electrodes 105 b and 106 b.

One end of the inductance device L1 is connected to the capacitorelectrode 104 a via the via hole conductor 103 a, and the other endthereof is connected to the capacitor electrode 104 b via the via holeconductor 103 b. One end of the inductance device L2 is connected to thecapacitor electrode 105 a via the via hole conductor 103 c, and theother end thereof is connected to the capacitor electrode 106 b via thevia hole conductor 103 f. One end of the inductance device L3 isconnected to the capacitor electrode 106 a via the via hole conductor103 e, and the other end thereof is connected to the capacitor electrode105 b via the via hole conductor 103 d.

Also, as illustrated in FIG. 34, the rear side of the wireless IC chip 5is provided with a coil-shaped electrode pattern 99 functioning as achip-side electrode pattern, and the inductance device L5 is defined bythis coil-shaped electrode pattern 99. Note that the surface of thecoil-shaped electrode pattern 99 is provided with a protective film,such as a resin or other suitable film. Thus, the inductance device L1defined by a coil-shaped electrode pattern functioning as a board-sideelectrode pattern, and the coil-shaped electrode pattern 99 aremagnetically-coupled.

The operations and advantages of the present nineteenth preferredembodiment are substantially the same as those in the seventeenthpreferred embodiment. That is to say, with this wireless IC device 1 s,a high-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit defined by theinductance device L2 and the capacitance devices C1 a and C1 b, and theLC series resonant circuit defined by the inductance device L3 and thecapacitance devices C2 a and C2 b) magnetically-coupled with theradiation pattern 20 is resonated, and only the reception signal havinga predetermined frequency band is supplied to the wireless IC chip 5. Onthe other hand, predetermined energy is extracted from this receptionsignal, the information stored in the wireless IC chip 5 is provided asan input signal, and reflection modulation is applied to this inputsignal with that energy as a driving source to obtain a transmissionsignal, and the transmission signal is matched with a predeterminedfrequency at the power supply circuit 16, following the transmissionsignal is propagated to the radiation pattern 20 from the inductancedevices L1, L2, and L3 of the power supply circuit 16 via magneticcoupling, and is transmitted and transferred from the radiation pattern20 to the reader/writer. Magnetic coupling is provided between the powersupply circuit 16 and the wireless IC chip 5 by the inductance devicesL1 and L5, thereby transmitting electric power and atransmission/reception signal.

Particularly, with the present nineteenth preferred embodiment, thepower supply circuit 16 includes the multiple LC resonant circuitsincluding the inductance devices L2 and L3 which are mutuallymagnetically-coupled, such that a frequency band to be used is increasedas with the seventeenth preferred embodiment.

Twentieth Preferred Embodiment

With a wireless IC device it according to a twentieth preferredembodiment, a power supply circuit board 110 is defined by asingle-layer board, and the equivalent circuit thereof is the same asthat in FIG. 3. That is to say, the power supply circuit 16 includes aLC series resonant circuit wherein the capacitance devices C1 and C2 areconnected to both ends of the inductance device L. The power supplycircuit board 110 is a ceramic board made of a dielectric member, and,as illustrated in FIG. 37, capacitor electrodes 111 a and 111 b areprovided on the front side thereof, and capacitor electrodes 112 a and112 b and a conductor pattern 113 are provided on the rear side thereof.The capacitor electrodes 111 a and 112 a define the capacitance deviceC1, and the capacitor electrodes 111 b and 112 b define the capacitancedevice C2.

The operations and advantages of the present twentieth preferredembodiment are substantially the same as those in the first preferredembodiment. That is to say, with this wireless IC device it, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit defined the inductancedevice L and the capacitance devices C1 and C2) magnetically-coupledwith the radiation pattern 20 is resonated, and only the receptionsignal having a predetermined frequency band is supplied to the wirelessIC chip 5. On the other hand, predetermined energy is extracted fromthis reception signal, the information stored in the wireless IC chip 5is provided as an input signal, and reflection modulation is applied tothis input signal with that energy as a driving source to obtain atransmission signal, and the transmission signal is matched with apredetermined frequency at the power supply circuit 16, following thetransmission signal is propagated to the radiation pattern 20 from theinductance device L of the power supply circuit 16 via magneticcoupling, and is transmitted and transferred from the radiation pattern20 to the reader/writer.

Particularly, with the present twentieth preferred embodiment, asillustrated in FIG. 38 and FIG. 39, the inductance device L is disposedso as to overlap the wireless IC chip 5 only partially in a plane view.Thus, most of magnetic fluxes that occur at the inductance device L arenot obstructed by the wireless IC chip 5, thereby obtaining anoutstanding rising edge of a magnetic flux.

Also, with the present twentieth preferred embodiment, as illustrated inFIG. 40, the power supply circuit board 110 on which the wireless ICchip 5 is mounted may be sandwiched with the radiation patterns 20 and20 on both sides thereof. Thus, the magnetic coupling efficiency betweenthe power supply circuit 16 and the radiation patterns 20 and 20 isimproved, and gain is also improved.

As for an arrangement wherein the radiation patterns 20 and 20 aredisposed on both sides of the power supply circuit board 110, theradiation patterns 20 and 20 may be disposed on one straight line on theX axis as illustrated in FIG. 41, and alternatively, may be disposed onthe X axis and Y axis as illustrated in FIG. 42.

Twenty-First Preferred Embodiment

A wireless IC device 1 u according to a twenty-first preferredembodiment is a device wherein the inductance device L is defined by ameandering-shaped line electrode pattern, and the equivalent circuitthereof is the same as that of in FIG. 3. That is to say, the powersupply circuit 16 includes a LC series resonant circuit wherein thecapacitance devices C1 and C2 are connected to both ends of theinductance device L. The power supply circuit board 110 is preferably aceramic single-layer board made of a dielectric member, and asillustrated in FIG. 43, capacitor electrodes 121 a and 121 b areprovided on the front side thereof, and capacitor electrodes 122 a, 122b and a meandering-shaped conductor pattern 123 are provided on the rearside thereof. The capacitor electrodes 121 a and 122 a define thecapacitance device C1, and the capacitor electrodes 121 b and 122 bdefine the capacitance device C2.

The operations and advantages of the present twenty-first preferredembodiment are substantially the same as those in the first preferredembodiment. That is to say, with this wireless IC device 1 u, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit defined by theinductance device L and the capacitance devices C1 and C2)magnetically-coupled with the radiation pattern 20 is resonated, andonly the reception signal having a predetermined frequency band issupplied to the wireless IC chip 5. On the other hand, predeterminedenergy is extracted from this reception signal, the information storedin the wireless IC chip 5 is provided as an input signal, and reflectionmodulation is applied to this input signal with that energy as a drivingsource to obtain a transmission signal, and the transmission signal ismatched with a predetermined frequency at the power supply circuit 16,following the transmission signal is propagated to the radiation pattern20 from the inductance device L of the power supply circuit 16 viamagnetic coupling, and is transmitted and transferred from the radiationpattern 20 to the reader/writer.

Particularly, with the present twenty-first preferred embodiment, theinductance device L is defined by a meandering-shaped conductor pattern123, which is efficient for transmission/reception of a high-frequencysignal.

Note that with the twentieth preferred embodiment and the presenttwenty-first preferred embodiment, the power supply circuit board 110may preferably be configured of a multilayer board, for example.

Twenty-Second Preferred Embodiment

With a wireless IC device 1 v according to a twenty-second preferredembodiment, as illustrated in FIG. 44 as an equivalent circuit, thepower supply circuit 16 includes the inductance devices L1 and L2 whichare mutually magnetically-coupled (illustrated by reference characterM), wherein one end of the inductance device L1 is connected to thewireless IC chip 5 via a capacitance device C1 and an electrode forconnection 131 a, and connected to one end of the inductance device L2via a capacitance device C2. Also, the other ends of the inductancedevices L1 and L2 are each connected to the wireless IC chip 5 via anelectrode for connection 131 b. In other words, the power supply circuit16 is configured so as to include an LC series resonant circuit definedby the inductance device L1 and the capacitance device C1, and an LCseries resonant circuit defined by the inductance device L2 and thecapacitance device C2, and both of the inductance devices L1 and L2 aremagnetically-coupled with the radiation pattern 20.

The power supply circuit board 10 is configured as illustrated in FIG.45. An electrode for connection 131 a is connected to a capacitorelectrode 133 via a via hole conductor 132 a, and the capacitanceelectrode 133 defines the capacitance device C1, facing a capacitorelectrode 134. Further, the capacitance electrode 134 defines thecapacitance device C2, facing a capacitor electrode 135. An electrodefor connection 131 b is connected to conductor patterns 136 a and 137 a,which are branched in a two-forked shape, through a via hole conductor132 b, the conductor pattern 136 a is connected to a conductor pattern136 b via a via hole conductor 132 c, further connected to a conductorpattern 136 c through a via hole conductor 132 d, further connected to aconductor pattern 136 d through a via hole conductor 132 e, and thisconductor pattern 136 d is connected to the capacitor electrode 134through a via hole conductor 132 f.

On the other hand, a conductor pattern 137 a is connected to a conductorpattern 137 b through a via hole conductor 132 g, further connected to aconductor pattern 137 c through a via hole conductor 132 h, and furtherconnected to a capacitor electrode 135 through a via hole conductor 132i. The conductor patterns 136 a, 136 b, and 136 c define the inductancedevice L1, and the conductor patterns 137 a, 137 b, and 137 c define theinductance device L2. Note that in FIG. 45, drawing of ceramic sheetsmade of a dielectric member is omitted.

The operations and advantages of the present twenty-second preferredembodiment are substantially the same as those in the first preferredembodiment. That is to say, with this wireless IC device 1 v, ahigh-frequency signal (e.g., UHF frequency band) radiated from theunshown reader/writer is received at the radiation pattern 20, the powersupply circuit 16 (the LC series resonant circuit defined by theinductance device L1 and the capacitance device C1, and the LC seriesresonant circuit defined by the inductance device L2 and the capacitancedevice C2) principally magnetically-coupled with the radiation pattern20 is resonated, and only the reception signal having a predeterminedfrequency band is supplied to the wireless IC chip 5. On the other hand,predetermined energy is extracted from this reception signal, theinformation stored in the wireless IC chip 5 is provided as an inputsignal, and reflection modulation is applied to this input signal withthat energy as a driving source to obtain a transmission signal, and thetransmission signal is matched with a predetermined frequency at thepower supply circuit 16, following the transmission signal is propagatedto the radiation pattern 20 from the inductance devices L1 and L2 of thepower supply circuit 16 via magnetic coupling, and is transmitted andtransferred from the radiation pattern 20 to the reader/writer.

Particularly, with the present twenty-second preferred embodiment, thecapacitor electrodes 133, 134, and 135, and the inductor conductorpatterns 136 a through 136 c, and 137 a through 137 c are disposedsubstantially in parallel to the radiation pattern 20. Therefore, themagnetic field formed by the inductor conductor patterns 136 a through136 c, and 137 a through 137 c is not obstructed by the capacitorelectrodes 133, 134, and 135, whereby the radiation properties from theinductor conductor patterns 136 a through 136 c, and 137 a through 137 care improved.

Twenty-Third Preferred Embodiment

A wireless IC device according to a twenty-third preferred embodimentincludes the power supply circuit board 10 including the power supplycircuit 16 having the equivalent circuit illustrated in FIG. 44. Thispower supply circuit board 10, as illustrated in FIG. 46, includessubstantially the same configuration as the power supply circuit board10 illustrated in FIG. 45, and additionally, a reflector (reflectionpattern) 138 and a wave director (waveguide pattern) 139 are provided ata portion where magnetic field is formed by the inductor conductorpatterns 136 a through 136 c, and 137 a though 137 c. The reflector 138and the wave director 139 adjust the radiation properties anddirectivity from the power supply circuit 16 to the radiation pattern20, and eliminate external electromagnetic influence to the greatestextent possible to stabilize the resonant properties.

The operations and advantages of the present twenty-third preferredembodiment are the same as those in the twenty-second preferredembodiment.

Twenty-Fourth Preferred Embodiment

With a wireless IC device 1 w according to a twenty-fourth preferredembodiment, a power supply circuit 150 is configured as adistributed-constant-type resonant circuit arranged in an inverted Fantenna configuration, which includes the equivalent circuit illustratedin FIG. 47. Specifically, as illustrated in FIG. 48, a power supplycircuit board 140 made of a ceramic multilayer board includes ahigh-side electrode 151 provided on a first plane 140 a, a built-incapacitor electrode 152, and a low-side electrode 153 provided on asecond plane 140 b. The high-side electrode 151 is electricallyconnected to the radiation pattern 20 by magnetic coupling andcapacitive coupling, and connected to a high-side terminal of thewireless IC chip 5 by a power supply pin 154. The low-side electrode 153is connected to a low-side terminal of the wireless IC chip 5, andconnected to the high-side electrode 151 via a short pin 155. Thecapacitor electrode 152 faces the high-side electrode 151 to formcapacitance, and connected to the low-side electrode 153 via a short pin156.

With this wireless IC device 1 w, a high-frequency signal radiated fromthe unshown reader/writer is received at the radiation pattern 20, thepower supply circuit 150 magnetically-coupled and capacitively-coupledwith the radiation pattern 20 is resonated, and only the receptionsignal having a predetermined frequency is supplied to the wireless ICchip 5. On the other hand, predetermined energy is extracted from thisreception signal, the information stored in the wireless IC chip 5 isprovided as an input signal, and reflection modulation is applied tothis input signal with that energy as a driving source to obtain atransmission signal, and the transmission signal is matched with apredetermined frequency at the power supply circuit 150, following whichthe transmission signal is transmitted and transferred from theradiation pattern 20 to the reader/writer.

Twenty-Fifth Preferred Embodiment

With a wireless IC device 1 x according to a twenty-fifth preferredembodiment, a power supply circuit 160 is configured as adistributed-constant-type resonant circuit arranged in an inverted Fantenna configuration, which includes the equivalent circuit illustratedin FIG. 49. Specifically, as illustrated in FIG. 50, a power supplycircuit board 140 made of a ceramic multilayer board includes ahigh-side electrode 161 provided on a first plane 140 a, and a low-sideelectrode 162 provided on a second plane 140 b. The high-side electrode161 is electrically connected to the radiation pattern 20 by magneticcoupling and capacitive coupling, and connected to a high-side terminalof the wireless IC chip 5 by a power supply pin 163. The low-sideelectrode 162 is connected to a low-side terminal of the wireless ICchip 5, and connected to the high-side electrode 161 via a short pin164.

With this wireless IC device 1 x, a high-frequency signal radiated fromthe unshown reader/writer is received at the radiation pattern 20, thepower supply circuit 160 magnetically-coupled and capacitively-coupledwith the radiation pattern 20 is resonated, and only the receptionsignal having a predetermined frequency is supplied to the wireless ICchip 5. On the other hand, predetermined energy is extracted from thisreception signal, the information stored in the wireless IC chip 5 isprovided as an input signal, and reflection modulation is applied tothis input signal with that energy as a driving source to obtain atransmission signal, and the transmission signal is matched with apredetermined frequency at the power supply circuit 160, following whichthe transmission signal is transmitted and transferred from theradiation pattern 20 to the reader/writer.

Twenty-Sixth Preferred Embodiment

With a wireless IC device 1 y according to a twenty-sixth preferredembodiment, a power supply circuit 170 is configured as adistributed-constant-type resonant circuit arranged in an inverted Lantenna configuration, which includes the equivalent circuit illustratedin FIG. 51. Specifically, as illustrated in FIG. 52, a power supplycircuit board 140 made of a ceramic multilayer board includes ahigh-side electrode 171 provided on a first plane 140 a, and a low-sideelectrode 172 provided on a second plane 140 b. The high-side electrode171 is electrically connected to the radiation pattern 20 by magneticcoupling and capacitive coupling, and connected to a high-side terminalof the wireless IC chip 5 by a power supply pin 173. The low-sideelectrode 172 is connected to a low-side terminal of the wireless ICchip 5.

With this wireless IC device 1 y, a high-frequency signal radiated fromthe unshown reader/writer is received at the radiation pattern 20, thepower supply circuit 170 magnetically-coupled and capacitively-coupledwith the radiation pattern 20 is resonated, and only the receptionsignal having a predetermined frequency is supplied to the wireless ICchip 5. On the other hand, predetermined energy is extracted from thisreception signal, the information stored in the wireless IC chip 5 isprovided as an input signal, and reflection modulation is applied tothis input signal with that energy as a driving source to obtain atransmission signal, and the transmission signal is matched with apredetermined frequency at the power supply circuit 170, following thetransmission signal is transmitted and transferred from the radiationpattern 20 to the reader/writer.

Twenty-Seventh Preferred Embodiment

With a wireless IC device 1 z according to a twenty-seventh preferredembodiment, a power supply circuit 180 preferably includes adistributed-constant-type resonant circuit arranged in an inverted Lantenna configuration, which includes the equivalent circuit illustratedin FIG. 53. Specifically, as illustrated in FIG. 54, a power supplycircuit board 140 made of a ceramic multilayer board includes ahigh-side electrode 181 provided on a first plane 140 a, a built-incapacitor electrode 182 and a low-side electrode 183 provided on asecond plane 140 b. The high-side electrode 181 is electricallyconnected to the radiation pattern 20 by magnetic coupling andcapacitive coupling. The capacitor electrode 182 faces the high-sideelectrode 181 to form capacitance, and connected to a high-side terminalof the wireless IC chip 5 at a power supply pin 184. The low-sideelectrode 183 is connected to a low-side terminal of the wireless ICchip 5, and connected to the high-side electrode 181 via a short pin185.

With this wireless IC device 1 z, a high-frequency signal radiated fromthe unshown reader/writer is received at the radiation pattern 20, thepower supply circuit 180 magnetically-coupled and capacitively-coupledwith the radiation pattern 20 is resonated, and only the receptionsignal having a predetermined frequency is supplied to the wireless ICchip 5. On the other hand, predetermined energy is extracted from thisreception signal, the information stored in the wireless IC chip 5 isprovided as an input signal, and reflection modulation is applied tothis input signal with that energy as a driving source to obtain atransmission signal, and the transmission signal is matched with apredetermined frequency at the power supply circuit 180, following whichthe transmission signal is transmitted and transferred from theradiation pattern 20 to the reader/writer.

Twenty-Eighth Preferred Embodiment

With a wireless IC chip 2 a according to a twenty-eighth preferredembodiment, as illustrated in FIG. 55, the wireless IC chip 5 and thepower supply circuit board 10 are mounted, disposed substantially inparallel on a rigid wiring board 8, and the power supply circuit board10 is adhered to the radiation pattern 20 with the adhesive agent 18.The power supply circuit board 10 is, for example, a board whichincludes the power supply circuit 16 illustrated in FIG. 2, and iselectrically connected to the wireless IC chip 5 by multiple conductors9 provided on the wiring board 8.

With this wireless IC device 2 a also, the power supply circuit 16 isprimarily magnetically-coupled with the radiation pattern 20, andperforms substantially the same operations as the first preferredembodiment to communicate with the reader/writer. Note that with thetwenty-eighth preferred embodiment, for the power supply circuit board10 those shown in the above respective preferred embodiments other thanthat shown in the first preferred embodiment can be used. This point canalso be applied to the following twenty-ninth preferred embodiment.

Twenty-Ninth Preferred Embodiment

A wireless IC device 2 b according to a twenty-ninth preferredembodiment is, as illustrated in FIG. 56, a device obtained by includingan arrangement wherein another radiation pattern 20 is adhered to thewiring board 8, and the wireless IC chip 5, power supply circuit board10, and wiring board 8 are sandwiched by the pair of radiation pattern20 in the device according to the twenty-eighth preferred embodiment.The operations thereof are substantially the same as those in thetwenty-eighth preferred embodiment, and particularly, the magneticcoupling efficiency between the power supply circuit 16 and theradiation patterns 20 is improved.

Thirtieth Preferred Embodiment

With a wireless IC device 2 c according to a thirtieth preferredembodiment, as illustrated in FIG. 57, a radiation pattern 22 having adouble closed loop shape is disposed in a symmetrical manner on thesurface of the resin film 21, and the power supply circuit board 10 thatmounts the wireless IC chip 5 is disposed on the center portion of theinner side loop of the radiation pattern 22.

With the present thirtieth preferred embodiment, the power supplycircuit board 10 is disposed adjacent to the radiation pattern 22without being adhered to the radiation pattern 22. The radiation pattern22 has a loop shape, so the linear length of the radiation pattern 22 isrelatively short. With this configuration, the power supply circuitboard 10 and the radiation pattern 22 are subjected to electromagneticinduction coupling, exchange of a signal is performed as with theabove-described preferred embodiments, and communication with thereader/writer can be performed. Also, minimal positional accuracy isrequired as long as the power supply circuit board 10 is disposedsubstantially at the center portion of the radiation pattern 22.

Thirty-First Preferred Embodiment

With a wireless IC device 2 d according to a thirty-first preferredembodiment, as illustrated in FIG. 58, a radiation pattern 23 having acombination of a meander shape, a loop shape, and a spiral shape isdisposed in a symmetrical manner on the surface of the resin film 21,and the power supply circuit board 10 that mounts the wireless IC chip 5is disposed at the center portion of the inner side loop of theradiation pattern 23.

With the present thirty-first preferred embodiment, the power supplycircuit board 10 is disposed adjacent to the radiation pattern 23without being adhered to the radiation pattern 23. The radiation pattern23 is a combination of a meander shape, a loop shape, and a spiralshape, such that the linear length of the radiation pattern 23 isrelatively short. With this configuration, the power supply circuitboard 10 and the radiation pattern 23 are subjected to electromagneticinduction coupling, exchange of a signal is performed as with theabove-described preferred embodiments, and communication with thereader/writer can be performed. Also, minimal positional accuracy isrequired regarding the placement of the power supply circuit board 10 aswith the above thirtieth preferred embodiment.

Note that the wireless IC device according to the present invention isnot restricted to the above-described preferred embodiments, and variousmodifications can be made within the scope thereof.

For example, the details of the internal configuration of the powersupply circuit board, the detailed shapes of the radiation pattern andfilm can be arbitrarily determined. Also, when connecting the wirelessIC chip on the power supply circuit board, processing other thansoldering bump may be used. Further, it is not required that the powersupply circuit board be rigid, and accordingly, the power supply circuitboard may be configured as a flexible substrate using an organic resinmaterial (e.g., polyimide or liquid crystal polymer).

While preferred embodiments of the present invention have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing the scope andspirit of the present invention. The scope of the present invention,therefore, is to be determined solely by the following claims.

1. A feed circuit, comprising: a resonant circuit having a predeterminedresonant frequency, wherein: the resonant circuit comprises a firstresonant circuit including a first inductor element and a secondresonant circuit including a second inductor element; the first inductorelement and the second inductor element are electronically connected toeach other in parallel and are magnetically coupled with each other; andthe feed circuit is configured to feed a signal with a specifiedfrequency to a radiation plate and/or to receive a signal with aspecified frequency from the radiation plate.
 2. The feed circuitaccording to claim 1, further comprising a plurality of terminals,wherein the first inductor element and the second inductor element areconnected in parallel between the plurality of terminals.
 3. The feedcircuit according to claim 1, wherein: one end of the first inductorelement is connected to one end of the second inductor element; and theother end of the first inductor element is connected to the end otherend of the second inductor element.
 4. The feed circuit according toclaim 1, wherein the first resonant circuit and the second resonantcircuit are distributed-constant resonant circuits.
 5. The feed circuitaccording to claim 1, wherein the first resonant circuit and the secondresonant circuit are concentrated-constant resonant circuits, the firstresonant circuit comprising a first capacitor element and the secondresonant circuit comprising a second capacitor element.
 6. The feedcircuit according to claim 5, wherein: the first capacitor element isconnected between the first inductor element and a terminal; and thesecond capacitor element is connected between the first inductor elementand the second inductor element.
 7. The feed circuit according to claim1, further comprising a multilayer substrate comprising a plurality ofdielectric layers or magnetic layers stacked one upon another, wherein acoil-shaped electrode pattern serving as the first inductor element anda coil-shaped electrode pattern serving as the second inductor elementare formed on a surface of or inside of the multilayer substrate.
 8. Thefeed circuit according to claim 1, wherein the radiation plate has anelectrical length that is an integer multiple of a half wavelength ofthe resonant frequency of the resonant circuit.